My car is overheating when driving instop and go traffic
My car is overheating. It only overheats in stop and go traffic, and will cool down when driving at highway speeds. Here is a list of things that I have tried: 1. Changed three relays in the engine bay, labeled Fan No. 1, 2, and 3. 2. Removed the relay for Fan No. 1, and used wire to jump it. 3. Tested both fans, plugging them directly into the battery, they both work. 4. Shorted the thermostat at the bottom of the radiator. 5. Tested the resistance of the thermostat on the engine block. 6. Drained/refilled the coolant in the radiator. There are 2 fans on the radiator. I've read that one
Experienced mechanics share their insights in answering this question :
Hi there, it sounds like you’re on the right path; it’s overheating because the fans aren’t turning on. We know your thermostat and water pump are both operating, otherwise it would most likely be overheating all the time. You said you replaced the relays, but what about the fuse? The power supply to the relays will be fused, and if that fuse is blown the fans will never turn on.
Check for power on both sides of the fuse with the key on. If the fuse is ok and you have power, check for power at the relay box. If you have power there and jumped the circuit with a wire before, and the fans still didn’t come on, then there is an open circuit somewhere, you just need to find it. If there is power at the relay and the fans work when you jump the relay, then you might have a failed engine coolant temperature sensor, which is what powers up the relay when the engine gets to a certain temperature. There could be another issue, though it’s hard to say without being able to see the car. To get a thorough, accurate diagnosis, I recommend contacting a professional to diagnose why your vehicle is overheating.
How to Identify and Fix Common car Problems ?
Our sources include academic articles, blog posts, and personal essays from experienced mechanics :
Broken Radiator Fan If sitting in traffic is the only time you experience an overheating engine, and the needle starts to move back out of the red once you speed up, the culprit is most likely a broken radiator fan. When you`re driving, the normal airflow will cool down the coolant in the radiator.
The most common reasons a Lexus ES300 is overheating are a coolant leak (water pump, radiator, hose etc.), the radiator fan, or a failed thermostat. Coolant leak (water pump, radiator, hose etc.)
In general, it`s because something`s wrong within the cooling system and heat isn`t able to escape the engine compartment. The source of the issue could include a cooling system leak, faulty radiator fan, broken water pump, or clogged coolant hose.
Car overheats when driving but not when idling
If your temperature gauge is fine until you make the car work, the most likely issue is coolant flow.
There could be a blockage, leak, or issue with the radiator fan. Your car`s water pump is broken. The water pump sends engine coolant throughout the coolant system. Yours might be suffering from a leak or a shifted pump shaft, both of which may cause overheating.
Overheating in Lexus cars are a common sight as there is insufficient air flow used for cooling the vehicle. As such, it could be necessary for you to install another radiator fan along with the extra fans directed towards components that are more susceptible to being damaged.
Insufficient coolant levels: Low coolant levels can impede the cooling system`s ability to regulate the engine temperature, especially during high-speed driving. Malfunctioning thermostat: A faulty thermostat may not open properly, hindering the flow of coolant and causing the engine to overheat.
There are a variety of reasons that a vehicle can overheat, such as cooling system leaks, blocked hoses from corrosion and mineral deposits, radiator issues or broken water pumps. Regular inspections may help avoid overheating issues down the road.
Relevant Questions and Answers :
the most relevant questions and answers related to your specific issue
Shifting from 2nd to 3rd, car stopped going fast. Now it won’t go at all.
ANSWER : It is possible that your clutch has failed. The sound you are hearing is likely due to the clutch not engaging with the engine due to it being worn. I would recommened having your transmission inspected by a qualified transmission expert to determine if your clutch requires replacement in order to resolve this issue. This inspection may require removal and partial disassembly of the transmission in order to verify that the clutch has failed.
Replaced alternator on car 2 times each time shows it’s charging 14v let car run for a little bit then test drive and car voltage
ANSWER : There are reports that the replacement alternators will not communicate with the engine computer and will not charge correctly. I recommend using only the manufacturer approved replacement part. It can be new or remanufactured but approved for use in the vehicle. Some lower cost alternators on the aftermarket will have charging problems since they will not communicate with the ECM on the vehicle and will stop charging.
I just got a new transmission put in my car and it drives and reverse but won’t go up hill.
ANSWER : This may be a sign of a faulty transmission control solenoid. As you know, automatic transmissions use pressurized hydraulic fluid to change gears. Every time a gear change is required, the car’s computer activates a transmission solenoid, which directs transmission fluid into the valve body to engage the correct gear. When this is faulty or not working properly, this can cause a delay in gear shifting or in some cases cause the car to not shift at all. I would recommend having an expert from YourMechanic come to your location to take the car for a test drive to more specifically determine the cause for this.
What isn’t working in my car? It’s overheating only when I’m stopped in traffic or in a drive-thru.
ANSWER : It sounds like you may have a cooling fan not working. The cooling fan draws air across the radiator to lower the temperature of the coolant. This occurs at a specific temperature and a fan switch, usually on the radiator, turns the fan(s) on when the coolant temperature reaches that threshold. When the car is moving, the fans are not needed as air flows across the radiator due to the movement. When you’re moving slowly or at a stop, the vehicle needs the fans to be operational to prevent overheating. If the fans are not coming on, the temperature of the coolant continues to rise until the vehicle ultimately overheats.
The root cause of the problem could be as simple as a fuse/relay, or it could be a fan switch, fan motor(s), or a wire harness issue. A quick visual inspection of the fuse can determine if that is the cause. Also, a check for battery voltage at the fan motors with the engine running and warmed up can determine if you have a fan motor inoperative. If there is battery voltage and good ground for the fan motors when the engine is hot, then the electrical system is operating properly and the fan motor is the culprit. I strongly recommend an experienced technician aid in diagnosing to prevent the replacement of unneeded parts. YourMechanic has several available technicians that can assist you with finding the cause of the car overheating issue, and provide an estimate and direction of repair.
i was driving and my oil light kept going off. Car had oil. Car wouldn’t accelerate. Car died. It does not turn engine over now.
ANSWER : It is very possible that the engine has been damaged beyond repair. Usually when the oil light goes on and the vehicle is low on oil, especially when a loud noise is heard right before the vehicle died, it is very likely that the engine is blown and would require replacement in order to continue driving the vehicle. I would recommend having the vehicle checked with a no start inspection. Consider YourMechanic as this service can be completed at your home or office.
Started Three days a go. When I drive the car it doesn’t go in to gears but shows AT.
ANSWER : This kind of reaction is often a sign of low transmission fluid or a faulty transmission control solenoid. As you know, automatic transmissions use pressurized hydraulic fluid to change gears. Every time a gear change is required, the car’s computer activates a transmission solenoid, which directs transmission fluid into the valve body to engage the correct gear. When this is faulty or not working properly, this can cause a delay in gear shifting or in some cases cause the car to not shift at all. This type of problem is amplified any time the transmission is low on fluid creating a drop in hydraulic pressure. I would recommend having a professional from YourMechanic come to your location to diagnose and inspect your vehicle.
My car is overheating when driving instop and go traffic
ANSWER : Hi there, it sounds like you’re on the right path; it’s overheating because the fans aren’t turning on. We know your thermostat and water pump are both operating, otherwise it would most likely be overheating all the time. You said you replaced the relays, but what about the fuse? The power supply to the relays will be fused, and if that fuse is blown the fans will never turn on.
Check for power on both sides of the fuse with the key on. If the fuse is ok and you have power, check for power at the relay box. If you have power there and jumped the circuit with a wire before, and the fans still didn’t come on, then there is an open circuit somewhere, you just need to find it. If there is power at the relay and the fans work when you jump the relay, then you might have a failed engine coolant temperature sensor, which is what powers up the relay when the engine gets to a certain temperature. There could be another issue, though it’s hard to say without being able to see the car. To get a thorough, accurate diagnosis, I recommend contacting a professional to diagnose why your vehicle is overheating.
My heat in my car stopped working two days ago and now my car is overheating. I put antifreeze in my car and it’s still overheating 2006 Pontiac Grand Prix
ANSWER : Hi there – you may have 2 related events here, a coolant leak, and a problem with the heater system. The current issue may be air inside the cooling system, which can cause overheating, and a lack of heater function. The lack of heater function could have 5 causes: the engine is not getting up to correct temperature (center of the gauge) due to a malfunctioning thermostat, the heater control valve is not letting hot coolant into the heater core, there is a restriction in the heater system that is preventing adequate hot coolant flow through the heater core, the heater fan is not working to transfer heat from the heater core to warm air for the passenger compartment, or the air blend doors inside the heater are not working properly to route warm air to the desired vents. I would recommend a heater system inspection](https://www.yourmechanic.com/services/heater-is-not-working-inspection) by a mobile, professional mechanic, such as one from YourMechanic, who will come to your location, diagnose this problem, give you an accurate assessment of damage and cost estimate for repairs.
